textproduct: Rapid City

KEY MESSAGES

- Warming trend as we move towards and through the weekend.

- Active northwest flow will bring chances for showers and thunderstorms today, and again on Saturday; severe weather is generally not expected at this time.

- Much warmer next week with increasing fire weather concerns due to increased winds and lower relative humidities.

UPDATE

Issued at 935 PM MDT Thu May 7 2026

Expect mainly dry conds the remainder of the night as diurnal convection dissipates. There could be a rouge shower/sprinkle later tonight, but given very dry LL's and lack of strong forcing, left pops out tonight. Warmer and breezy Fri. Lingering instability may support an isolated shower over the BH and SE in the afternoon, but given dry BL, not expecting much. The next impulse arrives later Friday night and will support showers into Sat across the SW third. Sharp cutoff expected in precip similar to today, with the NE half likely remaining dry. After seasonal temps Sunday, expect warm and dry conds most of next week.

DISCUSSION

(This Evening Through Thursday) Issued at 146 PM MDT Thu May 7 2026

Current Water Vapor and upper air models show northwest flow over the FA, as weak troughing sits over the Great Lakes region and upper ridge builds over the far western CONUS. Weak wave is riding the northwest flow currently over eastern MT into WY. 18Z Surface analysis has a frontal boundary associated with the wave stretching from eastern MT down into northeastern WY and down into far southwestern SD this afternoon. Radar currently shows some scattered showers with an isolated storm or two along the boundary in our western CWA. Temperatures currently sit in the upper 50s and 60s over the region, with most areas seeing light and variable winds.

Scattered light showers with some embedded thunderstorms will continue this afternoon into the evening, mainly along the boundary impacting the southwestern half of the forecast area. CAPE and Shear are on the lighter side, enough to spark some storms with maybe small hail and wind gusts 40-50 mph, but severe storms are not expected today. Some light QPF amounts possible through this afternoon, with the HREF probabilities for 0.1" or more showing the highest potential for northeastern Wyoming into the northern Black Hills (50-80%). Upper ridge over the far western CONUS progresses eastward into the Rockies Friday, promoting warmer temperatures, with highs reaching into the low 70s for much of the region. Mostly dry conditions are expected as well, however CAMs do try to paint some light spotty showers over the area, so have introduced some light PoPs for late Friday morning through early afternoon. Better precipitation chances return Saturday as another wave moves along the northwest flow through the FA. Current track of the wave points to a similar setup from today, with the southwestern 1/2 of the region seeing the best potential for showers/storms. Upper ridge slides over the Rockies and into the northern and central plains early next week, resulting in continued warmer temperatures and mostly dry conditions Sunday through middle of next week. Main forecast concern in this time frame will be increased fire weather conditions given the warmer temperatures and dry air. Currently Monday looks like the most impactful day with widespread critical fire weather potential.

AVIATION

(For the 06Z TAFS Through 06Z Friday Night) Issued At 949 PM MDT Thu May 7 2026

VFR conditions are expected through the TAF period.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.